Add locale based date formatting

[rhanton]

Adding additional date handler for providing a locale ISO-3166-1 string if you need formatting that is locale-specific called formatLocaleDate.

Adding a helper specifically for that. Open to ideas on naming etc. I'm also not an amazing node/js developer, so if someone can check my code/tests, that would be excellent.

Fixes #72

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (master@598efda). Click here to learn what that means.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             master       #73   +/-   ##
==========================================
  Coverage          ?   100.00%           
==========================================
  Files             ?         8           
  Lines             ?       201           
  Branches          ?         0           
==========================================
  Hits              ?       201           
  Misses            ?         0           
  Partials          ?         0           

Impacted Files	Coverage Δ
src/helpers/datetime.js	100.00% <100.00%> (ø)
src/helpers/math.js	100.00% <0.00%> (ø)
src/helpers/strings.js	100.00% <0.00%> (ø)
src/helpers/html.js	100.00% <0.00%> (ø)
src/helpers/conditionals.js	100.00% <0.00%> (ø)
src/H.js	100.00% <0.00%> (ø)
src/util/utils.js	100.00% <0.00%> (ø)
src/helpers/formatters.js	100.00% <0.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 598efda...aaf9a7b. Read the comment docs.

[kabirbaidhya]

@rhanton Thanks for the PR. Please do the above requested changes and we'll review again.

[rhanton]

@kabirbaidhya & @mesaugat if you can look at this again, it would be much-appreciated. We're hoping it will be possible to get a build with this code in the next week so we can pull it into some internal libraries and make some development timelines that are coming up soon. Thanks for your help!

[kabirbaidhya]

@rhanton Everything else looks good. Please do the requested changes and then we'll merge and do a patch. Thanks!

[kabirbaidhya]

LGTM. Thanks for your contribution 👍 🎉

[kabirbaidhya]

@rhanton v1.0.18 released.

[rhanton]

👏 Much thanks @kabirbaidhya ! I'm a Java developer by trade, so your input was incredibly helpful. Thanks for taking my team member Ryan Robinson's PR on "abs" a while back too.

[kabirbaidhya]

@rhanton For sure; I'm glad it helped. Please feel free for any kind of contributions in the future.